I pulled this info off the Secretary of State website

Flat Weight Trailers
Class/Gross Weight 1st Quarter
July 1 - Sept. 29 2nd Quarter
Sept. 30 - Dec. 30 3rd Quarter
Dec. 31 - Mar. 30 4th Quarter
Mar. 31 - June 30
TB (3,001-5,000 lbs.) $154 $118 $82 $46
TC (5,001-8,000 lbs.) $158 $121 $84 $47
TD (8,001-10,000 lbs.) $206 $157 $108 $59
TE (10,001-14,000 lbs.) $270 $205 $140 $75
TG (14,001-20,000 lbs.) $358 $271 $184 $97
TK (20,001-32,000 lbs.) $822 $619 $416 $213
TL (32,001-36,000 lbs.) $1,182 $889 $596 $303
TN (36,001-40,000 lbs.) $1,602 $1,204 $806 $408

Looks like it is a gradual decrease, I just replaced mine for $154